Study on Prevalence of eimeria species in layer Chicken of Kathmandu and Lalitpur Districts

Abstract

The present study was conducted in Machhegaun, Futung and Gothatar of Kathmandu district and Khumaltar of Lalitpur district from June 2002 to May 2003 with an aim to determine age-wise, site-wise and month-wise prevalence of coccidiosis as well as to identify the disease causing Eimeria species in Layer chicken. Five different species viz. E. tenella, E. acervulina, E. necatrix, E.maxima andE. brunetti responsible for coccidiosis were reported and the general prevalence was 24 percent. The highest number of positive cases (40%) was found with mixed infection.Species-wise infection with E. ten ellawas recorded to be the highest (25%), followed by E. acervulina(15%), E.necatrix (10%). E.maxima(7%) and E. brunetti (3%).Clinical symptoms of coccidiosis were diarrhoea,sometimes with blood tinged chocolate colour or bloody droppings. Post mortemlesion were intestineballoning,pin point haemorrhage, haemorrhagic enteritis, caecal distention and bloody in gesta. There were altogether 96 cases of coccidiosis of which 25%were caecal,35% intestinal and 40% mixed. Prevalence of coccidiosis was recorded inall the 12 months and four seasons, of the study period.The highest (38%) prevalence ratewas found in the month of July and the lowest (5.71%) in the month of October.The difference in monthly prevalence was insignificant (χ2=19.675, p<0.05).Similarly season wise prevalence showed the highest (35%) prevalence rate in the spring season followed by autumn (12%), winter (23%) and summer (25%),The difference in season-wise prevalence was insignificant (χ2=7.815, p>0.05). Theage-wise prevalence was thehighest (34.66%) in 61 weeks above chicken, followed by 30% in the 46-60 weeks age group, 22.5% in the 31-45 weeks age group,17.14% in the 0-15 weeks age group and 15.78% in the 16-30 weeks age group.The difference in age-wise prevalence was found to be insignificant (χ2= 9.488,P>0.05). Site-wise prevalence of coccidiosis was the highest 29.14% in Khumaltar,followed by 22.5% in Gothatar, 18.66% in Futung and 18.57% in Machhegaun. The difference in site-wise prevalence was found to be insignificant (χ2=7.15,P>0.05). Sporulation of oocyts of Eimeria species was completed after 72 hoursperiod at 24 0 c to 26 0 c, 48 hours period at 30°c and one week or more period below20°c inanaerobic condition. From histopathological sections, various degree of destructionof villi, lossof inflammatory cells and lymphocytes in the intestinal lumenand hemorrhages theintestinal epithelial tissue were found. Intestinal wall was also found to be thickeneddue to infection of above mentionedEmeriaspecies. Caecal coccidiosiswas found tobe more pathogenic in comparison to intestinal coccidiosis. Hence in poultry coccidia are ubiquitous but disease is most likely when young stocks are concentrated under condition which permit the accumulation and sporulation of large number of oocyst. The five species of Eimeria identified in this study are all pathogenic.